Bursitis pain comes from inflammation, so rest is first step

Q: I started using the rowing machine at our gym a few months ago. It's a good workout, but the outside of my left hip has started to ache. A friend says he experienced the same thing and it was bursitis. What is bursitis? What can you do to make it go away?

A: Bursitis is a painful condition that occurs when one or more of the small, fluid-filled sacs that help protect the joints become irritated or inflamed.

Known as bursae (the singular is bursa), these tiny cushions are made up of a thin membrane that secretes a slick, jellylike substance. Bursae help the structures of the joints — including bone, cartilage and connective tissues — glide over and around each other with minimal friction. The sites in the body where someone will often develop bursitis are the elbow, knee, shoulder and hip. The most common causes are overuse of the joint or physical injury. Infection can also cause bursitis.

With bursitis of the hip, two major bursae are typically involved. One is located at the inner part of the hip, near the groin area. This is the iliopsoas bursa. More often, it is the bursa located at the outside of the hip, near the bony point known as the greater trochanter, that becomes inflamed. This is called trochanteric bursitis. The main symptom is the hip pain that you described. It can sometimes extend beyond the hip to the outer part of the thigh.

Bursitis pain may start out sharp and quite pronounced, then gradually change into a more widespread and persistent ache. Hip bursitis is often worse at night, when lying down puts added pressure on the pelvic area. Rising from a chair or from a squat, climbing stairs or walking a long distance can also trigger the pain.

Diagnosis begins with a physical exam, and it may also involve imaging tests. When infection is suspected as the cause, fluid will be collected from the bursa and sent to a lab for testing.

Treatment focuses on taking steps to ease inflammation. This begins with rest. It is important for the individual to take a break from the activity associated with their case of bursitis. Over-the-counter pain and anti-inflammatory medications, such as aspirin and ibuprofen, are helpful in reducing swelling and managing pain. When necessary, more powerful anti-inflammatories may be prescribed.

Ice compresses, applied every four to six hours for about 20 minutes at a time, can also ease pain and swelling. It is possible, but not common, that it becomes necessary to drain the excess fluid from the bursa. If infection plays a role, that fluid is sent to a lab for analysis.

The good news is that bursitis often resolves over the course of a few weeks. A gentle stretching program, along with some easy strengthening exercises, can aid recovery. When pain persists, a doctor may prescribe a cortisone injection into the site. Cortisone usually offers quick relief from pain and inflammation.

If rest and anti-inflammatories don't help, it's a good idea to check in with your health care provider.

Q: We set up a carbon monoxide monitor in our new house, and it went off right away. It turns out the vent to the hot water heater was blocked. I've heard that even a little bit of carbon monoxide can make you sick. Why is it so dangerous?

A: Carbon monoxide, or CO, is a colorless and odorless gas. It is one of the byproducts of the combustion of carbon-based fuels. Common household fuels — such as natural gas, propane, oil, gasoline, kerosene and wood — release CO when they are burned. If the appliance burning the fuel isn't vented properly, carbon monoxide can begin to accumulate in the room and seep throughout the home.

Fuel-powered stoves, furnaces, water heaters, dryers, boilers, grills, lanterns and generators all produce CO. It is also emitted by wood-burning stoves, fireplaces and charcoal grills. Bottom line: Virtually any substance that contains carbon will produce carbon monoxide when it burns.

Even brief exposure to carbon monoxide can be fatal due to its chemical structure. Carbon monoxide binds to the hemoglobin in the blood far more easily than oxygen. That means when carbon monoxide is present in the air someone is breathing, it replaces the oxygen molecules in the blood. This starves the body of oxygen.

Cells and tissues that are denied oxygen will quickly suffer damage and begin to die. For example, brain cells deprived of oxygen begin to die after just three minutes. Beyond that, permanent brain damage begins to occur.

Symptoms of CO poisoning include headache, dizziness, blurred vision, suddenly feeling weak or tired, nausea, vomiting, confusion, shortness of breath, loss of muscle control and loss of consciousness. Individuals who survive CO poisoning can experience lingering effects, including ongoing problems with movement, cognition and memory.

It is estimated that carbon monoxide poisoning kills more than 420 people each year, and an additional 2,000 people require medical treatment. These numbers include infants, children and adults of all ages.

The CO monitor you installed in your home is an important safety feature. In many states, they are required by law. These monitors, which plug into electrical outlets and have backup batteries, are sensitive and accurate. They are affordable and widely available at retail stores and online.

A CO monitor works the same way as a smoke alarm. That is, it contains special sensors that detect the presence of carbon monoxide. If concentrations reach unsafe levels, it trips an alarm.

It is also important to take precautions against CO buildup, particularly in cooler months when outside ventilation is limited. Keep fireplace dampers wide open when burning wood, and wait for ashes to cool completely before closing them. Never heat a room with a gas stove or a gas or charcoal grill. Keep gas generators, which produce CO in their exhaust, at least 20 feet away from the house.

If CO ever does reach unsafe levels, the alarm in the monitor will go off. All humans — and don't forget the pets — in the home should go outside immediately to breathe fresh air. Call 911 to report the danger.

• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.